Most paranoid psychoses are chronic rather than episodic, but Schreber had an initial mental illness lasting from October 1884 to June 1885 from which he made a good recovery.

Thus the significant differences between LSD and schizophrenic psychoses appear to be in the affective nature of LSD psychosis and the greater incidence of delusions and auditory hallucinations in schizophrenics.

Only serious psychoses that required psychiatric consultation and/or treatment were considered as mental disturbances.